Are there still issues with https hotspot redirect?

I believe it was supposed to be solved in v9.9, but having just upgraded to v9.10, I'm still having issues when a user attempts to go to a https site before authenticating using a hotspot: using Mac Safari it takes 30s to load the captive portal (not using https is immediate) and on iOS it hangs seemingly forever. Is this still a known issue or is there something in the config that I've missed? I'm trying both secure hotspot and :9997/login methods